Substituted 1-aryl-2-napthoylamines and their use as microbicides

Abstract

1-Aryl-2-naphthoylamines of formula I are described ##STR1## wherein R.sub.1 is halogen, nitro, cyano, C.sub.1 -C.sub.6 alkyl that is unsubstituted or mono- or poly-substituted by halogen and/or C.sub.1 -C.sub.3 alkoxy, or is C.sub.3 -C.sub.6 cycloalkyl, OR.sub.4, NR.sub.5 R.sub.6, CO2R.sub.5, CONR.sub.5 R.sub.6 or NHCOR.sub.7, or wherein two adjacent positions in the nucleus are bridged by a methylenedioxy or ethylenedioxy group that is unsubstituted or mono- or poly-substituted by fluorine, wherein further R.sub.4 is hydrogen or C.sub.1 -C.sub.6 alkyl that is unsubstituted or substituted by C.sub.1 -C.sub.3 alkoxy or mono- or poly-substituted by halogen, or is C.sub.3 -C.sub.4 alkenyl, 2-propynyl, 3-halo-2-propynyl, ##STR2## or COR.sub.7, each of R.sub.5 and R.sub.6, independently of the other, is H or C.sub.1 -C.sub.4 alkyl, R.sub.7 is C.sub.1 -C.sub.4 alkyl and Z is O or NH, a and b denote the number of occupied positions in the respective 6-membered ring, and a is a number from 1 to 3 and b is a number from 0 to 3, the individual groups R.sub.1 being identical or different when the sum of a and b is greater than 1, X is O, S or NH, each of R.sub.2 and R.sub.3, independently of the other, is C.sub.1 -C.sub.6 alkyl that is unsubstituted or substituted by C.sub.1 -C.sub.4 alkoxy, halogen or by cyano, or is C.sub.3 -C.sub.7 cycloalkyl, C.sub.3 -C.sub.7 alkenyl or the radical ##STR3## wherein n is 0 or 1, or R.sub.2 and R.sub.3 are also together a C.sub.4 -C.sub.7 alkylene chain that together with the nitrogen atom may form a heterocycle that is unsubstituted or mono- or di-substituted by C.sub.1 -C.sub.4 alkyl, it being possible for one of the methylene groups in this chain to be replaced by O, S or NR.sub.7, and for R.sub.2 also to be hydrogen. The compounds of formula I have microbicidal activity and can be used advantageously for plant protection.